Interior vs exterior waterproofing methods
There is no single "best" way to waterproof a basement — it depends on the water source. This is a labeled method comparison, not a price list: enter the $/ft or $/sq ft from your own quote into the matching tool. Compare with the waterproofing cost, interior drain tile and exterior waterproofing calculators.
| Method | Best for | How it works |
|---|---|---|
| Interior drain tile + sump | Water already entering at the floor/wall joint | Sub-floor perforated pipe routes water to a sump pump; no exterior digging |
| Exterior excavation + membrane | Water pressure against the wall from outside | Dig to the footing, seal & drain the exterior — most invasive, needs a permit |
| Interior sealant / coating | Damp or minor seepage on the wall face | Masonry coating resists humidity; not a fix for active hydrostatic pressure |
A labeled comparison, not a price list. The right method depends on the water source — have it diagnosed, then enter the $/ft or $/sq ft from your quote into the matching tool.